TABLE 1.

Summary of glycoforms and their abundances found at the glycan epitopes of PGT135 by MALDI MS

Asn glycan site	Peptidea	Peptide mass [M+H]+	m/z		Glycoforme	% of total
			Observed	Calculated
N332	QAHCNLSRf,g	968.4	2,184.8b	2,184.9	M5	2
			2,346.9b	2,346.9	M6	<1
			2,509.0b	2,509.0	M7	1
			2,671.2b	2,671.0	M8	49
			2,833.3b	2,833.1	M9	47
N392	NSTW	507.2	1,583.4c	1,583.6	M4	1
			1,745.4c	1,745.6	M5	19
			1,907.4c	1,907.7	M6	<1
			2,069.5c	2,069.7	M7	2
			2,231.5c	2,231.8	M8	62
			2,247.4d	2,247.9
			2,393.5c	2,393.8	M9	16
			2,409.4d	2,409.9
N386	YCNSTQLFg	1,032.4	2,086.9b	2,086.8	M4	2
			2,249.0b	2,248.8	M5	7
			2,270.9c	2,270.8
			2,286.9d	2,286.9
			2,411.0b	2,410.9	M6	7
			2,433.0c	2,432.9
			2,449.0d	2,449.0
			2,573.1b	2,573.0	M7	33
			2,595.1c	2,594.9
			2,611.1d	2,611.0
			2,735.2b	2,735.0	M8	42
			2,757.1c	2,757.0
			2,773.1d	2,773.1
			2,897.3b	2,897.1	M9	9
			2,919.2c	2,919.0
			2,935.2d	2,935.1

^aThe Asn glycan sites are underlined.

^b[M+H]⁺.

^c[M+Na]⁺.

^d[M+K]⁺.

^eMx, ManxGlcNAc₂.

^fPyro-glu modification of glutamine (−17).

^gCarbamidomethyl modification of cysteine (+57).